The main objective of this work is to predict the two-phase flow dispersion in the bed of a hydrodesulfurization reactor. Physical properties are considered to remain constant, without including chemical reactions nor heat and mass transfer processes. Two different simulation tools have been used in this study. One of them is the commercial software Fluent, widely used in the field of Computational Fluid Dynamics, in which new drag and capillarity models not included in the commercial version of the software have been implemented. The second tool used is the domestic code Multiphase Flow Solver, written in Fortran programming language, which has been developed during this doctoral thesis, being one important goal of it. This code includes the models needed to describe the physical processes which describe the behavior of this type of multiphase flows and their dispersion in porous media.